Numerical control (“NC”) machines, such as a computer numerical control (“CNC”) machine, are automated machine tools that are operated by programmed commands encoded on a storage medium. The NC machine includes a machine tool (e.g., a spindle) that performs the machining and computer-aided manufacturing programs that drive the machine and position the spindle in three-dimensional space (e.g., multiaxis machining) with respect to a reference coordinate system of the machine.
During a machining operation, the part is mounted to a fixture and the fixture is loaded onto a machine bed of the NC machine. The position of the part relative to the machine bed is located and the machine is zeroed to properly position the machine tool in space relative to the location of the part. The part may then be machined (e.g., drill, route, cut, and/or trim). Often, the NC machine includes an indexing system used to repeatably locate the part relative to the fixture and to repeatably locate the fixture relative to the machine bed.
There are a number of drawbacks to current machining processes. For example, tooling fixtures can be highly complex, which is driven by tight tolerance requirements. Further, any part-to-fixture indexing and any fixture-to-machine bed indexing can be highly complex, which are also driven by tight tolerance requirements. This complexity can increase the cost and flow time required to produce an NC mill fixture, which can affect the offerability of a new product as well as the ability to meet customer emergent demands.
Moreover, the requirement to perform quality assurance of the machined part after the part is removed from the fixture drives additional cost, flow and impact to resources. For example, quality assurance can be performed by physically holding the part up to a component to which the part will be connected to determine if the machined features (e.g., holes and edges) align with the component geometry. If a machined feature does not properly align when the part is held up to the component, the part may be re-worked or scrapped, which interrupts the production cycle.
Accordingly, those skilled in the art continue with research and development efforts in the field of operating NC machines and performing quality assurance.